Derivative Financial Instruments and Hedging Activities Amounts Recognized in Net income (Details) - Interest expense - net [Member] - Fair Value Hedging [Member] - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Derivative designated as fair value hedges | $ 0 | $ 0 |
| Interest Rate Contract [Member] | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Derivative designated as fair value hedges | 20 | 113 |
| Related Long Term Debt Converted To Floating Interest Rates By Interest Rate Swaps [Member] | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Derivative designated as fair value hedges | $ (20) | $ (113) |